1. Field of the Invention
The invention relates to a transport device for electrical cables in a production station for the processing of electrical cables of a certain length, with at least one shifting-motion device, which can be moved stepwise in horizontal direction perpendicular to the axis of the cable ends, and which is provided with grippers which grip the cable ends, and which grippers can open and close, and which transport device further comprises a cable dump at the end of the shifting-motion device.
2. Brief Description of the Background of the Invention Including Prior Art
Such a transport device is a component of a production station for the processing of electrical cables of different lengths, different cross-sections, or different kinds, for the wiring of electrical plants in automobile and vehicular construction, for household appliances, or the like. The individual cables are automatically selected from a wire feeder and are cut in preselected lengths and are received by the transport device, which guides them stepwise along a processing line from processing station to processing station. During these steps, the cable ends are for example stripped and are provided with various connections and terminals, such as plug connectors, cable shoes, or the like. Both individual cable pieces as well as multipole connectors in bus-bar plug units can be automatically processed in desired production numbers for further processing.
A cable transport device in such a production station for the transport of cable sections perpendicular to their axes is taught, in addition to other related devices, in the German Patent Application Laid Open DE-OS 1,622,360. In particular, FIGS. 1 and 2 of DE-OS 1,622,360 illustrate in a side view an endless circulating transport system with a transport chain deflected by two chain wheels, where the transport chain comprises transporting clamps for gripping of an end of a cable section. In each case, two clamping jaws of the transport clamps are, in each case, tiltably supported between two clips and two hinge axles of an endless transport chain. The clamping jaws of the transport clamps are maintained closed by the force of a spring. In the region of the cable input and at the cable discharge, the clamping jaws are opened by control curves and by control rollers against the force of the spring. The drive of the transport chain is performed in steps, controlled by a specially formed worm thread gear driven by a drive motor provided with braking arrangements. Various processing stations are disposed along the upper strand of the transport chain next to the transport chain and above the transport chain, depending on the desired kind of processing of the respective end of a cable section. The reference teaches further that the complete transport device comprises two units, disposed in parallel next to each other, and that the parallel distance of the two chains can be adjusted by a shiftable support of one unit on a machine frame. The distance of the two units depends on the length of the cable sections to be processed and is adjusted by an adjustment device, not illustrated.
It is a disadvantage of this cable transport device that practically two equal mirror-like constructed transport units are necessary. A further disadvantage comprises that the lengths of the cables to be processed are limited and can be varied only between a minimum length, in case of a completely adjoining transport unit, and a maximum length, in case of a completely separated transport unit. Cable sections, with a length greater than 2 to 3 meters, cannot be processed with the taught transport device. Furthermore, two independent processing lines are required for the processing of the two cable ends.
The German Patent Application Laid Open DE-OS 3,340,744 teaches a further such cable processing station which also comprises a cable transport device realized as two endless transport chains, disposed in parallel to each other at a certain distance and deflected by two chain wheels in each case. Flush-aligned and releasable gripper pairs are arranged at the circumference of the two chains, which grip the two ends of each individual cable. The distance between the two chains can be varied and the cut-off cables, depending on their lengths, hang more or less down between the two transport chains and form a loop. In order to form a loop in the region of the cable feed, it is necessary to form the connection plate, serving as a cable guide between the two transport chains, as tiltable door or flap, which opens automatically when required and which closes again upon the feeding of a new cable. In addition, covering casings are required below the transport device between the two chains in order to prevent the downward hanging cable loops from getting stuck somewhere during the transport. A number of processing stations for the treatment of the two cable ends are provided successively at the two outsides of the transport chain. A step drive, actuated by an electric motor via a worm gear and a maltese cross-drive, moves the cable cuttings step by step from processing station to processing station.
It is a disadvantage of this transport device that also two independent processing lines are required for the processing of the two cable ends. In addition, this device is inadequate to transport longer cables without problems. Loops of cables, which are longer than, for example, 2 to 3 meters, would spread out on the floor without control and would slide or drag on the ground floor during the transport from processing station to processing station. A further disadvantage comprises that removal and discharge of individual cable strands is rendered very difficult in case of possible disturbances. In such cases, the complete bundle of the cable loops, disposed on top of each other and in part slid into each other, has to be removed in most situations.